Central offices known to provide ISDN Basic Rate Interface (BRI) access must be administered not only to define user subscribed transport services but also to provide, or deny access to service provider provided supplementary services. This is a complex operation, typically performed by an operator, and may be subject to operator error. During the administration process, the operator may manipulate many parameters, and any mis-administration may result in end-users being denied access to subscribed services, or suffering misoperation because of unexpected invocation of services which were not subscribed to by the user.